"Changing the operator on this condition will remove the non-default condition options currently set."
It's just telling you that the conditions options (under the dot-dot-dot button/icon) are going to be cleared because the operator is changing. That's because not every condition option is available for every operator. If you choose a Reactor-defined capability and attribute, it will recognize the operator's required type (so things like is TRUE and is FALSE will be allowed for attributes known to be boolean). When you use any extended attribute, like x_vera_anything.anything (the x_vera part being the clue that's an extended capability and attribute), that system's native type governs, and for Vera, that's a string, so is TRUE and is FALSE don't apply.
General recommendation is don't use the extended attributes when a Reactor-defined attribute is available.
To look beyond this, you'd need to post the attribute list for the device for starters. There's a Copy Attributes button in the entity detail. Use that, and paste the output here.
